NO donors are known to be useful for therapeutic utility, e.g., to prevent restenosis following angioplasty (Groves, P., et al., Cardiovascular Research 26, 615-619 (1992)), to inhibit platelets to prevent coagulation and thrombus formation (Groves, P., et al., Circulation 87, 590-597 (1993)) and to treat angina (Knight, et al., Circulation 95, 125-132 (1997)). NO donors are considered to have additional therapeutic utility in cancer, killing microbes and viruses, relaxing airways and intestinal smooth muscle (e.g., for treating asthma and esophageal spasms), in promoting erectile function and in treatment of heart failure and urinary incontinence.
NO donors are described in “Methods in Nitric Oxide Research,” edited by Feelisch, M., and Stamler, J. S., John Wiley & Sons, New York, 1996 at pages 71-115. These NO donors are O-nitroso and S-nitroso compounds, and C-nitroso compounds that are excluded from the invention herein.
Twenty-two additional C-nitroso compounds are described in Rehse, K, et al., Arch. Pharm. Pharm. Med. Chem. 331, 104-110 (1998). These compounds are of low molecular weight and are not water-soluble and were shown to be weakly active. Other C-nitroso compounds are described in Rehse, K, et al., Arch. Pharm. Pharm Med. Chem. 331, 79- 84 (1998); these are nitro-nitroso compounds and the specific compounds mentioned are excluded from the invention herein.
Other C-nitroso compounds which are old are 3-methyl-3-nitroso-2,4-pentanedione and 3-ethyl-3-nitroso-2,4-pentanedione. These compounds and their synthesis are described in Sklyar, Yu. E., et al., Khimiya Geterotsiklicheskikh Soedinenii 5, 70-73 (1969). These compounds are of low molecular weight and do not meet the definition of water solubility set forth hereinafter.